Low carbon solar water heating includes the following: If air is used as a heat transfer medium, there is one main supplier in UK. If water containing antifreeze is the heat transfer medium, there are many suppliers using either vacuum tubes or flat plate collectors to catch the sun.
Zero carbon solar water heating solutions tend to use water as the heat transfer medium. They include technologies such as Solartwin, which uses low flow pumps and microbore pipes, coupled with variable speed pumping. Other water based solar technologies use a drain-back system when frost threatens, in order to avoid freezing causing damage to its metal panels. This approach requires very diligent plumbing.
An alternative to metal pipes are flexible polymer ones which simply freeze without cracking - throughout the solar installation. Solartwin’s panel contains food grade flexible pipes like these. It plumbs directly into existing cylinders to maximise panel efficiency and stratification, and it can also be plumbed indirectly.
Solar keymark certified
Micropower council
Renewable Energy Association
Association for Environment Conscious Building